161757740 has 12 divisors (see below), whose sum is σ = 339691296. Its totient is φ = 64703088.

The previous prime is 161757731. The next prime is 161757769. The reversal of 161757740 is 47757161.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 161757694 and 161757703.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4043924 + ... + 4043963.

It is an arithmetic number, because the mean of its divisors is an integer number (28307608).

Almost surely, 2^161757740 is an apocalyptic number.

161757740 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161757740 is an abundant number, since it is smaller than the sum of its proper divisors (177933556).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161757740 is a wasteful number, since it uses less digits than its factorization.

161757740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8087896 (or 8087894 counting only the distinct ones).

The product of its (nonzero) digits is 41160, while the sum is 38.

The square root of 161757740 is about 12718.4016291356. The cubic root of 161757740 is about 544.8643042355.

The spelling of 161757740 in words is "one hundred sixty-one million, seven hundred fifty-seven thousand, seven hundred forty".